How to find the size of Boot section from original firmware !?

Installing and Using OpenWrt
1

Greetings!

I installed openwrt-ar71xx-generic-tl-wr710n-v2.1-squashfs-factory on TP-Link-WR710n_Ver2.1 device. but after installing I hadn't access to web user interface. I connected to device via SSH. I want to install original TPlink firmware again.

Problem: according to https://wiki.openwrt.org/toh/tp-link/tl-wr1043nd#back_to_original_firmware ,my tplink firmware (TP-Link-WR71n_Ver2.1) is contains word "boot". So I must to cut off parts of the image file before flashing.

Please help me to find the size for skip parameter in 'dd' command.

Links:
https://wiki.openwrt.org/doc/howto/generic.uninstall
https://wiki.openwrt.org/toh/tp-link/tl-wr1043nd#back_to_original_firmware
https://wiki.openwrt.org/doc/techref/flash.layout #(Go to Discovery (How to find out) section)

Thanks in advance.

2

The cut off is only needed if you flash the tp link firmware with the sysupgrade command from within openwrt/lede.

The size of the boot part will be 128k.
Use

dd if=fw_boot.bin of=fw.bin bs=1k skip=128

Which image have you installed?
Only stable releases did include the luci web interface by default.
The snapshots did not have a web gui, but could be installed with:

opkg update
opkg install luci
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3

Thanks you @juppin

I used information of below links:
https://wiki.openwrt.org/toh/tp-link/tl-wr710n
https://wiki.openwrt.org/toh/hwdata/tp-link/tp-link_tl-wr710n_v2.1

I think the Open-WRT firmware has not installed completely/correctly.
Also I haven't internet connection in TPLink__TL-WR710N to run your commands (opkg update AND opkg install luci); because I'm in SSH and configs lost.
I have wlan0 interface (via ifconfig), but I haven't /etc/interfaces file. even I can't connect to my wifi network via: iw dev wlan0 connect WiFi-MAX-Net

please help me to repair or roll-back the original firmware and try to install another WRT firmware.

Thanks you

4

Take a look into https://openwrt.org/docs/guide-user/base-system/basic-networking for configuring network.
And https://openwrt.org/docs/guide-user/network/wifi/basic for wireless configuration.

To setup wifi as client here an example for /etc/config/wireless

config wifi-device 'radio0'
	...
	option channel '1' # The channel of your ap

config wifi-iface
	option device 'radio0'
	option mode 'sta'
	option ssid 'WLAN' # The ssid of your ap
	option bssid 'XX:XX:XX:XX:XX:XX' # The bssid of your ap
	option encryption 'psk2+ccmp'
	option key 'password'
	option network 'lan'
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5

Thanks you so much

I'll try it.

6

Why not flash http://downloads.openwrt.org/releases/18.06.0-rc1/targets/ar71xx/generic/openwrt-18.06.0-rc1-ar71xx-generic-tl-wr710n-v2.1-squashfs-sysupgrade.bin from within your current running openwrt?

Upload this image with SCP (Windows: WinSCP) to your router to /tmp (ramdisk) and do:
sysupgrade -n /tmp/openwrt-18.06.0-rc1-ar71xx-generic-tl-wr710n-v2.1-squashfs-sysupgrade.bin

As i said, all stable releases did include a web interface by default... No need to get first back to stock fw.

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7

Excellent.

I'll try it. and I'll say you.
Thanks man.

8

Thanks Thanks.
But I have a question:
Which firmware is stable ?
https://wiki.openwrt.org/toh/hwdata/tp-link/tp-link_tl-wr710n_v2.1

  1. https://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/openwrt-ar71xx-generic-tl-wr710n-v2.1-squashfs-factory.bin !!??
  2. https://downloads.openwrt.org/snapshots/trunk/ar71xx/generic/openwrt-ar71xx-generic-tl-wr710n-v2.1-squashfs-sysupgrade.bin !!??

the upgrade firmware is for Web-Interface!? Why after installing factory, I can't login to device via web-interface (WUI) !?

could I install my own HTML template on this device !?
Is it possible for all supported WRT devices !?

last question: how you found the the size/value of skip parameter for dd command. please help me.

9

Everything here http://downloads.openwrt.org/releases/ is stable and everything here http://downloads.openwrt.org/snapshots/ is build from master branch and not stable.

You could install your own template, but is not that easy to create a theme...
Take a look at here: https://github.com/openwrt/luci/tree/master/themes

sysupgrade image is for upgrade from withing openwrt (sysupgrade command or luci web gui)
factory image is for flashing from stock / vendor firmware.

You can see the bootloader size on linux kernel log:
[ 0.740000] 0x000000000000-0x000000020000 : "u-boot"
0x20000 == 128kb

Because on non stable builds there is no web interface!

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